#ifndef EXCEPTIONS_H_
#define EXCEPTIONS_H_
#include <exception>
class ZeroDivision: public std::exception {
	virtual const char * what() const throw (){
		return "Division by zero!";
	}
};

class BadVariable: public std::exception {
	virtual const char * what() const throw (){
		return "Bad variable or constant name!";
	}
};

class OnlyVariable: public std::exception {
	virtual const char * what() const throw (){
		return "Only expression containing a variable can be used here!";
	}
};

class UnknownVariable: public std::exception {
	virtual const char * what() const throw (){
		return "Cannot find value of expression with free variables!";
	}
};

#endif /*EXCEPTIONS_H_*/
